CNG effect on engine life in Honda City ZX after running 1 Lac Kms

I am having Honda City ZX 2006 and had got DD Motors CNG fitted at 30,000Kms from an authorised fitment centre. Following are the maintenance / routine:

1. Running 5-6 Kms daily on petrol and monthly average running is 2300 Kms(~75Kms per day)

2. Getting the service done from Honda service centres at 10K intervals (that's what CNG fitter told me). They are using 3.6 lit of 10W30 engine oil.

3. Got the Lambda fitted after 3-4 months of Kit fitment but needs the kit tuning twice during 10K service period

Now after completing 116000 Kms I had by chance noticed the engine oil level dropped below minimum. I immediately rushed to nearest petrol pump and added 1 lit of oil (Mak 15W40 was available with them) so the level reached between minimum and maximum level.

Now after doing 600Kms I have noticed that around 100ml of oil consumed by the car. This does not seems to be normal. I have visited 3 mechanics and they have different view

First Mech- Engine needs an immediate overhall.

Second Mech - The engine started consuming oil but not visible in exhaust while full throtle. CNG kit in Honda City is not recommended or the other way Honda City engine is not good for CNG use and engine wear tear prematurely.

Third Mech - Not much problem as oil consumption is low, lets change the oil this time to Castrol Magnetic and watch the oil level regular intervals. Also keep the service period 5000 kms instead of 10000Kms.

I am looking for an expert opinion on this (oil consumption by engine) and recommeded best oil (is it castrol gtx cng) for CNG fitted Honda City please. Thanks in advance.

I think I would go with the third mechanic's advice. It would be a right thing to fill up the oil, and this time carefully keeping track of the consumption. Seems to be early for even a CNG engine to require an overhaul. You could also check the compression of each cylinder using a compression guage and accordingly decide. That will give you a better insight of the condition of each cylinder.

I have taken advice from another local reputed (non Honda) mechanic and he also suggested to get the engine oil changed at each 5000 Kms. I will be getting the engine oil, oil filter and air filter changed tomorrow.

But still undecided which oil will be the best for my cng fitted car - Mak or Castrol 10W30 or Castrol Magnatec 5W30 or Castrol GTX CNG 20W50 or Mak GE 20W50

Think oil consumption is quite high. For an engine rebuild, I would stick to Honda as they will have access to genuine spares as well as the correct technical knowledge to do the build. I think a compression test will reveal the exact amount of damage.

Hi, if ur engine does not emit smoke then there is no leakage in the gasket of the engine. Fiirstly, ur using wrong grade of engine oil. Any petrol/CNG engine requires 10W30 or 20W40 grade oil and not 15W40 or 20W50. so stick to 10W30 or 20W40 or 10W40. Do not mix different oil grades if short fall is there. You must monitor after every 1000 KM, how much oil consumption is there. Using CNG does not call for much oil consumption. Eng oil consumption happens when there is a leak in the head gasket. The engine oil travels thru various holes in the engine. There can be a possibility of faulty piston ring too. But in all the cases the oil will directly go to the combustion chamber and get burnt and we will see smoke out of exhaust....

Since last service done at 120000 kms I am topping up the engine oil nearly 500ml after running every 1000Kms. Is it ok to wait for another 2000-3000 kms before going for a rebuilt of engine. Please provide your expert opinion providing the pros and cons. Thanks in advance.

Hi, if ur given data is correct i.e the engine has run 1,20,000 Km and you are refilling every 1K then, i suggest you must consult Honda authorised service centre for engine overhauling.......best of luck

Hi, if ur given data is correct i.e the engine has run 1,20,000 Km and you are refilling every 1K then, i suggest you must consult Honda authorised service centre for engine overhauling.......best of luck